1. Field of the Invention
The present invention relates in general to an angular slide type cylindrical grinding machine and more particularly, to a novel positioning control of a sizing device used in such a grinding machine.
2. Description of the Prior Art
Generally, an angular slide type cylindrical grinding machine is used for simultaneously grinding a cylindrical surface and a shoulder side surface, which extends perpendicularly thereto, of a workpiece. A grinding wheel in such a grinding machine is formed at a circumferential surface thereof with a first surface of grinding the cylindrical surface and a second surface perpendicular to the first surface of grinding the shoulder side surface and is moved along a straight path extending at an acute angle .theta. to the axis of rotation of the workpiece. The infeed movement of the grinding wheel along the straight path causes the second surface of the wheel for shoulder side grinding to be displaced in an axial direction of the workpiece, and therefore, the axisl position of the workpiece must be adjusted in advance of the grinding of the workpiece. This axial position adjustment is, for example, such that when the cylindrical surface 17 of the workpiece W is finished to a diameter Di, as shown in FIG. 1, the shoulder side surface 16 finished simultaneously therewith is spaced by a distance .DELTA.l (i.e., Di/2.multidot.cotan .theta.) from an intersection P at which the rotational axis 14 of the workpiece W intersects a line 13 that extends through the juncture G of the wheel first surface 11 with the wheel second surface 12 in parallel relation with the straight path The method and apparatus for practicing such position adjustment of the workpiece is known by West German Patent Application N. 1,577,485.
Where sizing is used in such a grinding machine, the engaging points of the sizing device with the cylindrical surface 17 must be adjusted in connection with the adjustment of the workpiece axial position. The purpose of such adjustment of the engaging point S may be to prevent interference between the workpiece shoulder side surface 16 and a pair of feelers of the sizing device, to make the fellers engage the workpiece cylindrical surface 17 at a position apart from a keyway formed on the cylindrical surface, or to make the feelers engage a portion of the cylindrical surface 17 which does not contact a portion of the grinding wheel 10 where local wear occurs. However, since the sizing device is mounted on a bed of the grinding machine and the workpiece is supported on a work table slidable on the bed, movement of the workpiece in its axial direction results in changing the relative position of the sizing device to the workpiece shoulder side surface.